Electric signal system



Aug'. 6, 1929. T. H.- THOMAS 1,723,29

ELECTRIC SIGNAL SYSTEM Filed Aug. 8. 1927 l l @C "if INVENTOR l THOMAS H THOMAS s BY M y@ ATTORNEY Patented Aug. e, 192e.

UNITED STATES PATENT OFFICE.l

THOMAS H. THOMVAS, OF EDGEWOOD, PENNSYLVANIA, ASSGNOR TO THE W'ESTNG- HOUSE AIR BRAKE COMPANY, GF WLMERDCNG, PENISYLVANIL, A CGRPQEATION OF PENNSYLVANIA.

ELECTRIC SIGNAL SYSTEM.

Application led August 8, 1927.

This invention relates to signal systems and more particularly to an electricsignal system adapted for use on railway trains.

An object of my invention is to provide an electric train signal system by the .use ot which a trainman may signal the engineman -from any car ot' a train and by which the enginemans reply signal will be received by the trainman only at the station from which the signal was sent by the trainman or at any other station or stations the trainman may choose.

In the accompanying drawing, 1 is a diagrannnatic view of an electric signal system embodying my invention, and illustratingr the enginemans switch in one position, and Figs. 2 and 3 ai'e diagrammatic sectional views showing` the enginemans switch in two other positions.

As illustrated in the accompanying,` drawing, the locomotive or controlled car of a train may be provided with an electric battery 1 or any other desired source of electric current, a signal indicating device such as a buzzer 2 and an enginemans switch comprising a rotatable member 4 which is provided with a contact 5 adapted in one position to electrically connect terminal contacts 6 and 7 which are connected to ground at 8 and to one terminal of the buzzer 2, respectively, and in another position to electrically connect terminal contacts 9 and 10, which are connected to the positive terminal of the batter 1 and to a train wire 11, respectively. he negative terminal of the battery 1 is connected to ground at 12. The train wire 11 is connected to the other ter minal of the buzzer 2.

Each of the cars ot' a train may be provided with an electric battery 12 or any other suitable source of electric current, a signal indicating device such as a buzzer 13, a switch device 14 and a jack device 15.

The switch device 14 comprises a casing; 16 containing a sliding` Contact member 17, which member is provided with an operating stem 18 adapted to be operated, in one direction, by a lever 19 having operating arms 20 and 21,'each .having an operating cord 22 attached thereto. This lever 19 is adapted to fulcrum around pins 23 and 24 which are so disposed and mounted in the casing` 16, that when the arm 20 is operated the lever turns about the pin 23 and when the arm 21 Serial No. 211,327.

is operated the lever turns about the pin 24 and in either case the le 7er dcpresses the stem 1S and the contact member 17, rotative movement ot the member being prevented by a pin mounted in the casing` engaging in a slot toi-ined in the member. f

The member 17 is provided with a contact 25 and is normally maintained in the position shown in the drawing by the action of a. spring 26. When the member 17 is moved, by the lever 19, a predetermined distance, the end ot said member will engage a stop toi-med on a plug27 having screw-threaded connection with the casingr,Y 1G. When the member 17 is in this position the contact 25 will connect terminal contacts 28 and 29 connected to the positive terminal ot the battery 12 and to a tine 30 of the ack 15, respect-ively. The negative terminal. isconnected to ground at 3l.

The jack 15 is also provided with tines 32 and 33 which are connected to one terminal ot the buzzer 13 and to the ground at 34., respectively. The other terminal of the buzzer is connected to the train wire 11. The tines 30 and 32 of the jack, normally contact with each other and are so formed that they are adapted to receive the end portion of a plug 35 between them. The tine 33 is normally out of Contact with the tine 32, but when the plug' 35 is inserted between the tines 30 and 32, the tine 32 is moved into contact with the tine 33.

Assuming the several parts o1 the signal system te be in the positions as shown in Fig. 1 of the drawing, sii-es to sienal the engineman, the trainman pulls the cord 22 which causes the lever 19 .to operate to depress the stem 18 and contact member 17 a suiiicient distance that the lower end of the member engages the stop on the plug 27 secured to the casing 16, in which position the contact 25 electrically connects the terminal contacts 2S and 29 and as the tines 30 and 32 of the jack 15 are in contact with each other, and the contact 5 of the enginemans switch 3 connects the terminal contacts 6 and 7, current will flow from the positive terminal of the battery 12, through the buzzer 13, train wire 11., buzzer 2 and switch 3 to ground at 8, and as the negative terminal of the battery is connected to ground at 31, the circuit is complete and both buzzers will operate. While the trainand the trainman de` CTX 'Contact With the tine 33 of the jacir,

man maintains the Contact member 17 depressed, the engineman may signai the trainmnn by rotating the member so that the Contact 5 Will be moved out of engagement with the terminal Contact 6 which lends ground, as shown in F ig. 2 of the drm-ing,

thus opening the circuit and interrupt the operation ot 'the buzzers. By rotnti g the member L1 beck and forth, the circuit is opened and ciosed, so that the cnf may thus cause any predetermined f" u sound at the tramnmns station on the tram. VTitb the severed pa *te oi the sigimi system TTie: 1

in the positions as shown in of the drawing, and the trainmandesires he System to be in readiness toet he nii-gb receive, Winch t i at his stationv on tile train, any SigL ai may be initiated by the engineman, he the ping 35 between the tines 30 and 32 jack, which causes the tine 32 to mov 13, and jack 15 to ground et 34, and as the negative terminal of the battery 1 is connected to ground at 12, a circuit is completed and the bunzer 13 will operate.

ving now described my invention, what l' claim as newvand deeire to secure by Letters Patent, is

in a train signal system, the combination with a train Wire, of a signaling unit on one car of a trein comprising a signal device connected to said train Wire, a` source of electric current, and :L switch device 1paving one posi tion for connecting seid Source to Seid train i 're and :mother position for connecting sind Signe-1 device to ground, and another signeiing unit on another car of the train con'iprieing a second signal device connected to said 'ein ire, e second source o'f electric cn nt, and two switch devices, one of seir Switch devices having n position for connecting said second source of current to said second signal device and the other switch device havnw u. position for connecting said Second signai Levice to ground and for opening the circuit through which said Second Signal device connected to saidA second source of c went.

Mi testimony whereof I have hereunto set my band. 

